Extending Chord Selection in Diatonic Major / Minor Keys
This chart demonstrates the full range of chords available in a given major or minor key using the technique of tonicisation (temporarily establishing an alternative tone centre within the key – a “mini-modulation” for a short duration). This technique is used extensively in Jazz and Classical music to expand the range of the major/minor system to it’s utmost. The chart below can be used to facilitate composition and reharmonisation, both in the considered and ad-hoc sense s(e.g. scoring a composition/arrangement vs spontaneous chord substitution in Jazz Improvisation). This harmonic technique can be expanded to any genre!
The following classes (functions) of additional chords are used:
1. Secondary Dominants and their tritone substitutes (“V” & “bII” function)
e.g. D7 (Secondary Dominant) and Ab7 (Tritone Substitute), resolving to G in key of C major
2. Secondary Supertonics (“iim7 & ii0/7” function)
e.g. F#m7 to resolve to B7 to Em in key of C
3. Secondary Subdominants (“IV & iv function) also known as borrowed chords – “borrowed” from the key’s parallel major/ minor scale counterpart)
e.g. Fm in key of C or F in key of C minor
Scale Degree Names in Major Key Scale Degree Names in Minor Key
I Tonic i Tonic ii Supertonic ii Supertonic iii Mediant bIII Mediant IV Subdominant iv/IV Subdominant V Dominant v/V Dominant vi Submediant bVI/vi Submediant bVII Subtonic vii Leading Note vii Leading Note
C Major
F /Fm G/Gm A/Am B/Bm C/Cm D/Dm E/Em Secondary Subdominants (IV) Dm7 Em7 F#m7 Gm7 Ami7 Bm7 C#m7 Secondary Supertonics (ii) G7 A7 B7 C7 D7 E7 F#7 Secondary Dominants (V) Db7 Eb7 F7 Gb7 Ab7 Bb7 C7 Tritone Substitutes (bII) Cma7 Dm7 Em7 Fma7 G7 Am7 B0/7 Diatonic Chords: Major i ii iii IV V vi vii Numerals for Diatonic Chords
C Minor
F/Fm G/Gm Ab/Abm Bb/Bbm C/Cm Db/Dbm D/Dm Eb/Ebm E/Em Secondary Subdominants (IV) D0/7 E0/7 F0/7 G0/7 A0/i7 Bb0/7 B0/7 C0/7 C0/7 Secondary Supertonics (ii) G7 A7 Bb7 C7 D7 Eb7 E7 F7 F#7 Secondary Dominants (V) Db7 Eb7 E7 Gb7 Ab7 A7 Bb7 B7 C7 Tritone Substitutes (bII) Cmi#7 Dm7b5 Ebma7 Fm7 Gm7 Ab Bb7 Diatonic Chords: Natural Minor Do7 Ebma7#5 Fo7 G7b9 Abo7 Bo7 Additional Chords: Harm. Minor Dm7 F7 G9b13 A0/7 B0/7/B7alt Additional Chords: Mel. Minor i ii bIII iv V/v bVI vi bVII vii Numerals for Diatonic Chords